[whatwg] Data store readability in drag/dragend

Can we make the drag data store available in read only mode in drag or
dragend? Presumably they are getting fired at the source element that
originally set the data in dragstart, so it's not a security issue.
http://www.onemanmmo.com/index.php?cmd=newsitem&comment=news.1.83.0 is one
person's attempt to work around the current limitations of the system.

Daniel